Grain-heater



. (No Model.) I- 2Sheets -Sheet l. J. STEVENS 85 J. R. DAVIS, Jr.

Gra,-in Heater Patented Jan. 4,188].

N. PETERZ, PHoYu-LITNOGRAPHER, WASHXNGTON. D C.

2 Sheets--Sheet 2. J. STEVENS 85 J-. R. DAVIS, Jr.

(No Model;)

Grain Heater. No. 236,272; Patented Jan. 4,1881.

N. PETERS, FHDTD-LITHOGRAFHER, WAHXNGTON. D. C

UNTTED STATES PATENT FFICE.

JOHN STEVENS AND JOHN R. DAVIS, JR, OF NEENAH, WISCONSIN.

GRAIN-HEATER.

SPECIFICATION forming part of Letters Patent No. 236,272, dated. January 4, 1881.

Application filed October 19,1880. (NomodeL) N To all whom it may concern:

Be it known that we, JOHN STEVENS and JOHN It. DAVIS, Jr., of Neenah, in the county of Winnebago and State of Wisconsin, have invented certain new and useful Improvements in Grain-Heaters, of which the following is a specification.

As heretofore usually constructed, grainheaters have been furnished with a continuous coil of tubing leading from the induction to the eduction pipe, through which the steam or hot air is passed and between which the grain falls. In these, owing to the nece'ssarylength of the coil, the heat is variable, being greatest at the top and gradually decreasing, from radiation and condensation, along the length of the tube.

Our invention is designed to afford a uniform heat from the entrance to the exit of the grain; and it consists in combining with a series of short horizontal pipes arranged to interrupt the grain in its fall, fed from a common steam or hot-air trunk,and provided with immediate returns orducts leading directly from the outer ends to an exhaustchamber, a hopper whereby the grain is discharged in a stream along the length of said pipes, and

guides or deflectors which gather in the seattered grain and lead it into contact with the underlying pipes of the series; and in the yarious other combinations and details of construction hereinafter described and claimed.

In the drawings, Figure l is a side elevation of a device embodying our invention, partly in section to show the arrangement of the pipes and inlet and exhaust trunks. Fig. 2 is a horizontal section on the line A B of Fig. 1. Fig. 3 is a vertical transverse section on the line as w of Fig. 1. Fig. 4 is a vertical transverse section on the line 3 y of Fig. 1. Fig. 5 is an end elevation, and Fig. 6 is an enlarged detail view.

Thedevice which we have chosen to illustrate ourinvention and represented in the drawings is adapted particularly for use with roller-mills such as are now commonly known in milling; but with slight and obvious modifications it may be applied to grinding-burrs or to the heating or drying of grain preparatory to reduction by any of the ordinary milling processes. It is adapted to be fed with steam or hot air, (preferably the former,) and it will be understood that hereinafter when the word steam is usedit is intended to include any suitable known heating agent. The steam is introduced through a pipe, E, furnished with a suitable cock for the proper regulation of the quantity, into the top of the steam-trunk F, located at one end of the heater and running from top to bottom thereof. From this trunk a series of parallel pipes extend horizontally toward and nearly to the opposite endof the heater. These are arranged, as shown, alternately in pairs and single pipes, the two pipes of each pair being placed on the same level and some distance apart, and the sin glepipes below and centrally between those of the over and under lying pairs.

Between the trunk F and the main chamber G of the heater is an exhaust chamber, H, parallel with the trunk and of about the same dimensions, and from near the bottom of this exhaust chamber leads the eduction pipe 1, through which the dead steam flows from the heater. The inner wall, g, of the exhaustchamberis bored with uniform perforations, to admit the passage of the pipes f into the main or heating chamber, each perforation being concentric with, but of greater diameter than, the pipe passing therethrough. Screwed into these perforations so as to open into the exhaust chamber, and extending therefrom to the opposite head of the heating-chamber, where their ends are closed, are pipes h, of such diameter as to leave a free space between their internal surfaces and the exterior surfaces of the pipesf, which they ensheath.

The steam and exhaust trunks are both furnished with plugs i, by means of which they can be flushed when necessary. We have shown them as comprised within a single casting, K, which forms one head of the heatingchamber, the other head, K, being a solid casting recessed alongits face to correspond with the perforations in the wall of the exhaustchamber, so as to receive the ends of thelarger pipe it into such recesses, and thereby close them, suitable packing, It, being used to make tight joints. If desired, however, the tubes may be formed with solid ends, as represented in Fig. 6. The opposing faces of the two heads are channeled or ribbed vertically on each side as at k it, from the top nearly or quite to the bottom, to receive the plates L,

which form the side walls of the heatingchamber. Two or more of the pipes h are passed entirely through the head K, and when the parts have been put together are closed by caps or plugs l, which serve as ties to conmeet the whole structure.

Above the heating-chamber is placed a hopper, M, running its whole length, and as grain is fed from this it falls upon the single heating-pipeimmediately beneath, and is scattered toward the sides of the chamber and against inclined deflecting-plates m m. which guide it to the pair of pipes next below, from whence it falls upon the succeeding single pipe and is again scattered, checked by other deflectingplates, guided to the second pair of heatingpipes, and so on until it has passed 0W3? all the pipes of the series. The first pair of deflecting-plates leads from the mouth of the hopper past the first single pipe, to the top of the first pair of pipes, striking each pipe at its crest or apex, to leave no angle for the lodgment of grain. The next pair of plates leads from the exterior of the first pair of pipes past the second single pipe to the crest of the second pair of pipes, the third in like manner from the second to the third pair of pipes, until the last pair of plates form the chute through which the heated grain makes its exit. They may be soldered to the pipes or may fit into grooves in the head-pieces, and, together with the side plate, L, may be so arranged as to he slipped in or taken out after the pipes and head-pieces have been tied together, so as to be readily replaced when worn.

The course of the steam or heated air through the pipes is indicated by the arrows. It first flows from the steam-trunk through the pipes fto the termination of the latter near the farther ends of the concentric pipes h, and then returns through these to the exhaust-chamber. Thus each pipe is simultaneously heated by a current of steam from a common body, and the heat will therefore be uniform throughout the series.

The flow of steam may be reversed, so as to make that chamber which we have indicated as the steam-trunk the exhaust-chamber and the other the steam-trunk 5 but the arrangement described and shown in the drawings is the preferable one.

Instead of the concentric pipes, single pipes of U form may be used, one end terminating in the steam-trunk and the other in the exhaust-chamber. By placing these so that one arm shall be vertically beneath the other the alternation of pairs and single pipes can readily be brought about and substantially uniform heating obtained. Such an arrangement, although for some reasons not so desirable as the first, we consider within the principle of our invention.

'hen the heater is intended for use in connection with roller-mills its length will be the length of the feed to said rolls and its hopper will be practically the hopper of the rolls. The stream of grain, as it enters between the rolls after passing through the heater, will be of the same width and quantity as when itfell from the hopper. For other mills the heater may be made shorter or furnished with adouble series of pipes and deflecting-plates, or the delivery-chute maybe made of a funnel shape to deliver the grain within a narrower limit; or other obvious expedients may be adopted.

\Ve claim as our invention-- 1. In a grain heater, the combination of a steam-trunk, an exhaust-chamber, a series of alternating pipes fed independently from the steam-trunk, and havingiminediate returns to the exhaust-chamber, a hopper arranged to discharge the grain in a stream along the lengths of said pipes, and guides or deflectors which direct the scattered grain so as to bring it into contact with the underlying pipes in the series.

2. The combination, in a grain-heater, of the series of heating-pipes placed alternately singly and in pairs, and having immediate returns, and the deflecting-plates leading from the exterior of each pipe of the overlying pair to each pipe of the pair beneath.

3. The combination, in a grain heater, of the series of pipes leading from a common steam-trunk and placed alternately singly and in pairs, the concentricreturn-pipes opening into a common exhaust-chamber, and the deflecting-plates leading from the exterior of each outer pipe of the overlying pairs to each outer pipe of the pair beneath. I

4. The combination, in a grain-heater, with the pipes screwed into one head thereof, of the socketed opposing head, whereby the farther ends of said pipes are closed.

5. The combination of the heads formed with flanges to receive the side plates of the heating-chamber, the pipes screwed into one head and received in sockets in the other, and caps applied to the projecting ends of certain of said pipes to tie the structure together.

6. The combination of the head K, formed with steam-trunk and exhaust-chamber, and flanged as described, the pipes leading from the steam-trunk, the concentric return-pipes screwed into the wall of the exhaust-chamber, the head K, having sockets, flanges, and perforations, the side plates, L, and the caps or ties l, substantially as described.

7. The head K, formed as a casting, with sockets to receive and close the ends of the steam-pipes, perforations to admit the passage of the tying-pipes, and grooves to receive and support the side plates of the heating-chamber, substantially as described.

JOHN STEVENS. JOHN R. DAVIS, JR. Witnesses:

ALEX. MCNAUGHTON, E. N. HOLBROOK. 

